<!DOCTYPE html>
<html lang="en" xmlns:wicket="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <wicket:head>
        <script type="text/javascript">
            function foo(){
                alert("Hello,World!");
            }
        </script>
    </wicket:head>
</head>
<body>
    <wicket:panel>
        <a href="#" onclick="foo()">Click me!</a>
    </wicket:panel>
</body>
</html>